The present invention relates,to a new and improved pump assembly and more specifically to a pump assembly in which excess fluid is bypassed from an outlet to an inlet passage.
During operation of a pump assembly, it is a common practice to bypass fluid at a relatively high pressure from an outlet to an inlet passage. As the bypassed fluid enters and flows along the inlet passage, the pressure in the bypassed fluid is quickly reduced. Thus, the pressure in the bypassed fluid may be reduced from more than 2,000 psi (gauge) to less than 100 psi (gauge).
This rapid pressure reduction in the bypassed fluid tends to cause localized cavitation in the fluid. The bypassed fluid is concentrated in a stream which may impact against the side of the inlet fluid passage. The combined effects of impacting of the stream of bypassed fluid against the housing and cavitation in the bypassed fluid tends to erode the housing.